In a manufacturing process of semiconductor apparatuses and flat panel displays (FPDs), a variety of vacuum apparatuses are utilized. To perform a process management of the vacuum apparatuses, quadrupole mass analyzers are used. The mass analyzers are apparatuses for measuring partial pressures of a variety of substances included in the gas to be analyzed according to their mass-to-charge ratio (mass number/charge number). In addition, in recent years, the mass analyzers are used in a wide variety of fields such as an assaying of materials, an analysis of biopolymer compounds such as protein, and security. Therefore, there is an increasing demand for mass analyzers.
A quadrupole mass analyzer energizes a filament as an ion source portion in a mass spectrometer tube to cause thermions to be emitted, to thereby ionize a gas and generate ions. In an ion detector for detecting ionized ions, a secondary electron multiplier tube made of a Cu—Be alloy, an aluminum oxide (AlO), and the like is often utilized.
However, faulty observance of instructions and directions for use of mass analyzers leads to a failure in a filament or an ion detector. Furthermore, each filament and ion detector has an operating life. If the operating life is exceeded, it is not possible to obtain correct measurement. Therefore, to prevent a failure in, to identify the operating life of, and to extend the operating life of a filament and an ion detector, for example configurations as follows are disclosed.
A filament is capable of glowing only when the pressure is not greater than approximately 1 Pa. At pressures more than that, there is a possibility that the filament will be broken. Therefore, in Patent Document 1, to prevent a failure in a filament and an ion detector, a pressure detection portion of a vacuum gage is placed in a mass analyzer, to thereby prevent a break in a filament. In Patent Document 2, an overcurrent prevention circuit for a filament is added, to thereby prevent a break in a filament. In Patent Document 3, a filament current is detected to estimate the operating life of a filament.
On the other hand, in Patent Document 4, detection of unnecessary ions is avoided to extend the operating life of an ion detector. In Patent Document 5, a gas flow rate of a calibration gas is determined on a mass spectrum pattern for optimization of the flow rate, to thereby prevent a deterioration in sensitivity of an ion detector and to thereby detect contamination in an ion source portion. In Patent Document 6, materials and configurations used for an ion detector are selected, to thereby extend the operating life of the ion detector.
Furthermore, a mass analyzer is capable of being operated only at pressures not more than the use pressure as described above. Therefore, if the pressure is high, a pumping system called a differential pumping system may be used, which is added to the mass analyzer to construct a mass spectrometry unit. In this case, a failure in the pumping system may lead to a failure in the mass analyzer. To prevent this, for example in Patent Document 7, each of a preventive maintenance solution before the occurrence of an anomaly of a pump, a solution to a fault at the occurrence to the anomaly, and a risk aversion solution after the occurrence of the anomaly according to the states before and after the anomaly, is displayed, output as an electric signal or as speech, to thereby perform a preventive maintenance.    Patent Document 1: Japanese Unexamined Patent Application, First Publication No. 2004-349102    Patent Document 2: Japanese Patent No. 3734913    Patent Document 3: Japanese Unexamined Patent Application, First Publication No. H07-151816    Patent Document 4: Japanese Unexamined Patent Application, First Publication No. H09-22681    Patent Document 5: Japanese Unexamined Patent Application, First Publication No. H08-321277    Patent Document 6: Japanese Unexamined Patent Application, First Publication No. H09-171083.    Patent Document 7: Japanese Unexamined Patent Application, First Publication No. 2004-177213    Patent Document 8: Japanese Unexamined Patent Application, First Publication No. H05-275052    Patent Document 9: Japanese Unexamined Patent Application, First Publication No. H05-109860
In a manufacturing process of semiconductor apparatuses, FPDs, and the like, an etching apparatus, a chemical vapor deposition (CVD) apparatus, or the like is used. When a mass spectrometry unit is used in such apparatuses, a corrosive/halogen-based gas introduced into the etching apparatus or a gas filled in the CVD apparatus for depositing a metal/insulating film has an adverse influence on a filament or an ion detector. For example, if a filament is exposed to a corrosive-halogen-based gas, a coating made of yttrium oxide on the surface of the filament comes off, finally bringing about a possibility of the occurrence of an anomaly such as a break in the filament and the stopping of an emission current flowing between the filament and the grid. Furthermore, a secondary electron multiplier tube as an ion detection portion is for generating secondary electrons by causing ions to collide with its metal surface at a high speed. Therefore, if a metal/insulating film is deposited on the metal surface, there is a possibility that secondary electrons are less likely to be generated. Therefore, in Patent Documents 8 and 9, there is proposed a technique that enables reactive gas monitoring even during a deposition operation. Note that a gas that decreases the function of a specific portion in a mass spectrometry unit such as a corrosive/halogen-based gas or a gas for depositing a metal/insulating film will be hereinafter referred to as a “specific gas.”
While the operating life and performance of mass spectrometry units have improved and their demand has grown, there are increasing number of users who use mass spectrometry units without regard to instructions and directions for use. To be more specific, different mass spectrometry units should be used according to their applications such as the gases and apparatuses that they are to measure. However, sometimes, they are used without regard to the applications. Therefore, it sometimes happens that an unexpected specific gas is introduced into a mass spectrometry unit. As a result, filaments, ion detectors, and the like often suffer from a failure before they reach the end of their operating life.
As described above, a filament, an ion detector, and the like are parts with an operating life, and hence, require regular replacement. However, the time for their replacement is subject to change according to the condition of use and the circumstances of use. Therefore, it is difficult to determine the correct time for their replacement. If the filament, the ion detector, or the like is replaced after it is unusable and a correct measurement is impossible, there arises a problem of an extended period in which use of the mass spectrometry unit is suspended. In addition, if the filament, the ion detector, or the like is replaced in advance although it is still usable, there arises a problem of a loss of resources and costs.
Furthermore, when the filament, the ion detector, or the like is replaced, or when the pump is overhauled, there is a possibility that a specific gas is deposited on the filament, the ion detector, or the like. Therefore, it is required to secure the safety of the worker. Conventionally, the worker starts working after asking the user about the introduction history of a specific gas each time the replacement or the overhaul is done. This has resulted in extra time in replacement work.
In the case where the mass spectrometry unit is used for an etching/CVD apparatus, the mass spectrometry portion and the pump used in the differential exhaustion system are heated even during measurement, to thereby prevent deposition of metal/insulating matter. Through the pump, a purge gas (for example, N2) is introduced to dilute a corrosive-halogen-based gas. After completion of the measurement, it is not necessary to heat the mass spectrometry tube and the pump and to purge the pump if the aforementioned corrosive/halogen-based gas, the aforementioned gas for depositing a metal/insulating film, or the like is not introduced therein. Nevertheless, if the heating of the mass spectrometry tube and the pump, and the purge of the pump are continued in operation, there arises a problem in that electric power and gas are wasted.